EFFECT OF Staphylococcus epidermidis ON Pseudomonas aeruginosa BIOFILM IN MIXED-SPECIES CULTURE

Staphylococcus epidermidis and Pseudomonas aeruginosa, are clinically relevant pathogens that often produce biofilms. To investigate the co-survivability of S. epidermidis and P. aeruginosa in mixed cultures biofilm and planktonic form, it is important to understand more about the interspecies interaction of both species. The interspecies interaction was analyzed using streak and drop agar plate assay, cell viability assay (CFU), spectrophotometry-based method, and microscopic analysis. The findings suggest that both cells and supernatant of P. aeruginosa inhibit the planktonic growth of S. epidermidis. The cell viability result shows that PAO1 biofilm cells were decreased by 88%, and SE biofilm cells were increased by 75% concerning their control. Opposite to the P. aeruginosa, the S. epidermidis biofilm and EPS matrix were found to increase in mixed culture biofilm, which was further confirmed by microscopic analysis. In contrast, differential agar media result shows that the reduction in the biofilm (CFU/ml) of P. aeruginosa is independent of S. epidermidis cells concentration. Finally, the effect of the supernatant on biofilm was investigated, and it found that S. epidermidis biofilm was enhanced while P. aeruginosa biofilm was reduced in the presence of partner bacterial supernatant, which indicated that S. epidermidis in biofilm mode could hinder the biofilm formation of P. aeruginosa. The outcomes show that the culture supernatant of S. epidermidis can be used to prevent P. aeruginosa associated biofilm infections

Antagonistic Compounds Producing Plant Growth Promoting Rhizobacteria: A Tool for Management of Plant Disease

Agriculture is facing struggle to meet the various confront of reducing plant diseases for an increasing world population food security. Great quantities of synthetic fertilizers and pesticides are required for high productivity which can damage ecosystem structures and functions, including the soil microbial community which plays an important role in agriculture sustainability. Soil is an excellent niche of growth of much plant growth promoting rhizobacteria. PGPR are naturally occurring soil bacteria that aggressively colonize in plant roots and play a vital role in crop protection, growth promotion and in the improvement of soil health. Scientific researchers involve multidisciplinary approaches to understand adaptation of PGPR, effects on plant physiology and growth induced systemic resistance, biocontrol of plant pathogens and biofertilization. The primary mechanism of biocontrol by PGPR involves the production of antibiotics such as carboxylic acid, 2,4-diacetyl phloroglucinoloomycin,pyoluteorin,pyrrolnitrin,kanosamine,zwittemycin-A and pantocin. A cascade of endogenous signals such as sensor kinases, N-acyl homoserine lactones and sigma factors regulates the synthesis of antibiotics. Some of these antibiotics have broad spectrum against many plant pathogens like fungi, viruses and bacteria, affecting crop plants. These antibiotics also serve as determinants in triggering induced systemic resistance (ISR) in the plant system

Further evidence that a terminal drought tolerance QTL is also associated with reduced salt uptake

AbstractEarlier, we established that a major drought tolerance QTL on linkage group 2 of pearl millet is also associated with reduced salt uptake and enhanced growth under salt stress. Present study was undertaken to re-assess the performance of drought tolerant (PRLT 2/89-33) and drought sensitive (H 77/833-2) parents along with two QTL-NILs (ICMR 01029 and ICMR 01040), under salinity stress specifically imposed during post-flowering growth stages when plants had developed their ion sinks in full. Time course changes in ionic accumulation and their compartmentalization in different plant parts was studied, specifically to monitor and capture changes conferred by the two alleles at this QTL, at small intervals. Amongst different plant parts, higher accumulation of toxic ion Na+ was recorded in roots. Further, the Na+ concentration in roots of the testcross hybrid of the drought-sensitive parent (H 77/833-2) reached its maximum at ECiw 15dSm−1 within 24h after salinity imposition, whereas it continued to increase with time in the testcross hybrids of the drought tolerant parent PRLT 2/89-33 as well as those of its QTL-NILs (ICMR 01029 and ICMR 01004) and reached at its maximum at 120h stage. Comparison of differential distribution of toxic ions in individual leaves revealed that Na+ ions were not uniformly distributed in the leaves of the drought-tolerant parent and drought-tolerant QTL-NILs; but accumulated preferentially in the older leaves, whereas the hybrid of the drought-sensitive parent showed significantly higher Na+ concentration in all main stem leaves irrespective of their age. Dynamics of chlorophyll and proline concentration variation studied under salt stress at late flowering stages revealed a greater reduction, almost twice, in both leaf chlorophyll and proline concentrations in younger leaves in the hybrids of the sensitive parent as compared to the tolerant parent and QTL NILs. Imposition of salinity stress even at flowering stage affected the yield performance in pearl millet, wherein higher yield was recorded in drought tolerant parent and the two QTL-NILs compared to drought sensitive parent

Molecular Markers Associated with Agro-Physiological Traits under Terminal Drought Conditions in Bread Wheat

Terminal drought stress poses a big challenge to sustain wheat grain production in rain-fed environments. This study aimed to utilize the genetically diverse pre-breeding lines for identification of genomic regions associated with agro-physiological traits at terminal stage drought stress in wheat. A total of 339 pre-breeding lines panel derived from three-way crosses of ‘exotics × elite × elite’ lines were evaluated in field conditions at Obregon, Mexico for two years under well irrigated as well as drought stress environments. Drought stress was imposed at flowering by skipping the irrigations at pre and post anthesis stage. Results revealed that drought significantly reduced grain yield (Y), spike length (SL), number of grains spikes−1 (NGS) and thousand kernel weight (TKW), while kernel abortion (KA) was increased. Population structure analysis in this panel uncovered three sub-populations. Genome wide linkage disequilibrium (LD) decay was observed at 2.5 centimorgan (cM). The haplotypes-based genome wide association study (GWAS) identified significant associations of Y, SL, and TKW on three chromosomes; 4A (HB10.7), 2D (HB6.10) and 3B (HB8.12), respectively. Likewise, associations on chromosomes 6B (HB17.1) and 3A (HB7.11) were found for NGS while on chromosome 3A (HB7.12) for KA. The genomic analysis information generated in the study can be efficiently utilized to improve Y and/or related parameters under terminal stage drought stress through marker-assisted breeding

Lasmiditan: new drug for acute migraine

Migraine is ranked by the World Health Organization as the world’s second leading cause of disability. The current state of knowledge suggests that migraine is a neuronal process involving activation and sensitization of the trigeminal nociceptors and the trigeminocervical complex, as well as cortical spreading depression and abnormal brainstem activity. The present non vascular etiological basis has opened a new horizon in the treatment of acute migraine targeting the trigeminal pathways. Lasmiditan, a highly selective 5-HT1F receptor agonist, acts on the trigeminal system without causing vasoconstriction because of its low affinity for 5-HT1B receptors. The compound belongs to a new class of drugs “ditans” and its mechanism of action is neuronal without evidence of vasoactive effects as seen with triptans. It lowers plasma protein extravasation decreasing the neurogenic inflammation of the dura and suppress neuronal firing within the trigeminal nucleus caudalis. Also, 5HT1F agonists have shown to decrease c-fos activity within trigeminal nucleus thereby reducing the level of synaptic activation. The onset of action of lasmiditan is fast, shows rapid absorption, oral bioavailability of 40% and linear pharmacokinetics. Most common adverse reactions seen are dizziness, paresthesia, somnolence, nausea, fatigue and lethargy with dizziness being the most recurrently reported adverse event. Clinical trials for lasmiditan to date have been positive, and maiden results suggest that lasmiditan may be a new safe and effective option for acute migraine treatment, especially for patients refractory to or unable to tolerate triptans, and/or for patients with pre-existing cardiovascular disease. With Eli Lilly and Co. having already applied for US FDA approval in Nov 2018, lasmiditan may soon be a new addition to the mounting armoury of drugs against migraine

Current advances in genomics and gene editing tools for crop improvement in a changing climate scenario

The unprecedented global climate change has severely impacted our environment and engendered severe threats to agricultural productivity (Shahzad et al., 2021; Cinner et al., 2022; Ozdemir, 2022). This has led to the emergence of new races of plant pathogens and insect pests, accentuated abiotic stresses, depleted water resources and shrunken arable land, posing grave challenges to the food security of an ever-increasing global population (IPCC Sixth Assessment Report, 2022). The advantages offered by the Green Revolution of the mid-1960s are also fading away, resulting in a fragile food system (Davis et al., 2019; John and Babu 2021). Agriculture today faces newer challenges exacerbated by genetic erosion, the narrow genetic base of commercial crops and environmental degradation. There is an urgent need to make agriculture more resilient and sustainable while still continuing to develop high-yielding, stress-resistant and climate-smart crop varieties

Integration of gene-based markers in a pearl millet genetic map for identification of candidate genes underlying drought tolerance QTLs

BACKGROUND: Identification of genes underlying drought tolerance (DT) quantitative trait loci (QTLs) will facilitate understanding of molecular mechanisms of drought tolerance, and also will accelerate genetic improvement of pearl millet through marker-assisted selection. We report a map based on genes with assigned functional roles in plant adaptation to drought and other abiotic stresses and demonstrate its use in identifying candidate genes underlying a major DT-QTL. RESULTS: Seventy five single nucleotide polymorphism (SNP) and conserved intron spanning primer (CISP) markers were developed from available expressed sequence tags (ESTs) using four genotypes, H 77/833-2, PRLT 2/89-33, ICMR 01029 and ICMR 01004, representing parents of two mapping populations. A total of 228 SNPs were obtained from 30.5 kb sequenced region resulting in a SNP frequency of 1/134 bp. The positions of major pearl millet linkage group (LG) 2 DT-QTLs (reported from crosses H 77/833-2 × PRLT 2/89-33 and 841B × 863B) were added to the present consensus function map which identified 18 genes, coding for PSI reaction center subunit III, PHYC, actin, alanine glyoxylate aminotransferase, uridylate kinase, acyl-CoA oxidase, dipeptidyl peptidase IV, MADS-box, serine/threonine protein kinase, ubiquitin conjugating enzyme, zinc finger C- × 8-C × 5-C × 3-H type, Hd3, acetyl CoA carboxylase, chlorophyll a/b binding protein, photolyase, protein phosphatase1 regulatory subunit SDS22 and two hypothetical proteins, co-mapping in this DT-QTL interval. Many of these candidate genes were found to have significant association with QTLs of grain yield, flowering time and leaf rolling under drought stress conditions. CONCLUSIONS: We have exploited available pearl millet EST sequences to generate a mapped resource of seventy five new gene-based markers for pearl millet and demonstrated its use in identifying candidate genes underlying a major DT-QTL in this species. The reported gene-based markers represent an important resource for identification of candidate genes for other mapped abiotic stress QTLs in pearl millet. They also provide a resource for initiating association studies using candidate genes and also for comparing the structure and function of distantly related plant genomes such as other Poaceae members

Identification of Genetic Loci and Candidate Genes Related to Grain Zinc and Iron Concentration Using a Zinc-Enriched Wheat ‘Zinc-Shakti’

The development of nutritionally enhanced wheat (Triticum aestivum L.) with higher levels of grain iron (Fe) and zinc (Zn) offers a sustainable solution to micronutrient deficiency among resource-poor wheat consumers. One hundred and ninety recombinant inbred lines (RILs) from ‘Kachu’ × ‘Zinc-Shakti’ cross were phenotyped for grain Fe and Zn concentrations and phenological and agronomically important traits at Ciudad Obregon, Mexico in the 2017–2018, 2018–2019, and 2019–2020 growing seasons and Diversity Arrays Technology (DArT) molecular marker data were used to determine genomic regions controlling grain micronutrients and agronomic traits. We identified seven new pleiotropic quantitative trait loci (QTL) for grain Zn and Fe on chromosomes 1B, 1D, 2B, 6A, and 7D. The stable pleiotropic QTL identified have expanded the diversity of QTL that could be used in breeding for wheat biofortification. Nine RILs with the best combination of pleiotropic QTL for Zn and Fe have been identified to be used in future crossing programs and to be screened in elite yield trials before releasing as biofortified varieties. In silico analysis revealed several candidate genes underlying QTL, including those belonging to the families of the transporters and kinases known to transport small peptides and minerals (thus assisting mineral uptake) and catalyzing phosphorylation processes, respectively

Glycemic Control and Its associated Determinants among Type II Diabetic Patients at Tertiary Care Hospital in North India

Introduction: Good glycemic control has been defined as achieving a target of fasting plasma glucose level of between 80 and 110 mg/dl, or glycosylated haemoglobin (HbA1C) of <7.0%. Poor glycemic control is highly correlated with chronic conditions related to the damaging effects of hyperglycaemia, resulting in serious complications. To restrict and delay the complications of diabetes mellitus, good glycemic control is essential. Objective: To identify the determinants associated with poor glycemic control among Type 2 diabetes mellitus patients. Method: A cross sectional study was conducted among 403 confirmed type 2 diabetic patients who attendedone of the tertiary care hospitals of North India over a period of six months (July- December 2021). The collected data was analysed using IBM SPSS version 28. Chi-square test was applied to compare various determinants of glycemic control. A p-value of <0.05 was considered to be statistically significant. Results: Out of 403 participants, 57.6% had poor glycemic control of diabetic condition. Higher age of participants, illiteracy, being overweight, having positive history of smoking and alcohol, longer duration of diabetes, participants taking both oral and insulin treatment for diabetes, taking medicine irregularly were the significant determinants of poor glycemic control. Conclusion: Higher percentage(57.6%) of poor glycemic control was observed in the study.To improve the glycemic control, efforts should be made towards improving modifiable factors like overweight, smoking, alcohol, regularity of medication etc. Good lifestyle interventions help in control of poor glycemic control

Exploring potential of pearl millet germplasm association panel for association mapping of drought tolerance traits

A pearl millet inbred germplasm association panel (PMiGAP) comprising 250 inbred lines, representative of cultivated germplasm from Africa and Asia, elite improved open-pollinated cultivars, hybrid parental inbreds and inbred mapping population parents, was recently established. This study presents the first report of genetic diversity in PMiGAP and its exploitation for association mapping of drought tolerance traits. For diversity and genetic structure analysis, PMiGAP was genotyped with 37 SSR and CISP markers representing all seven linkage groups. For association analysis, it was phenotyped for yield and yield components and morpho-physiological traits under both well-watered and drought conditions, and genotyped with SNPs and InDels from seventeen genes underlying a major validated drought tolerance (DT) QTL. The average gene diversity in PMiGAP was 0.54. The STRUCTURE analysis revealed six subpopulations within PMiGAP. Significant associations were obtained for 22 SNPs and 3 InDels from 13 genes under different treatments. Seven SNPs associations from 5 genes were common under irrigated and one of the drought stress treatments. Most significantly, an important SNP in putative acetyl CoA carboxylase gene showed constitutive association with grain yield, grain harvest index and panicle yield under all treatments. An InDel in putative chlorophyll a/b binding protein gene was significantly associated with both stay-green and grain yield traits under drought stress. This can be used as a functional marker for selecting high yielding genotypes with 'stay green' phenotype under drought stress. The present study identified useful marker-trait associations of important agronomics traits under irrigated and drought stress conditions with genes underlying a major validated DT-QTL in pearl millet. Results suggest that PMiGAP is a useful panel for association mapping. Expression patterns of genes also shed light on some physiological mechanisms underlying pearl millet drought tolerance